Various forms of closure apparatus for screwing on screw closures are known and are conventional. In order to ensure that the screw closure is not screwed on too tightly, which could possibly result in damage, such closure apparatuses are provided with a torque-dependent clutch to limit the maximum torque which can be transmitted.
In practice, virtually only slipping clutches are used for this purpose. Slipping clutches of this kind are known for example, from published German patent application No. 24 36 993. Mechanical torque-limiting assemblies have also already been proposed, for example, U.S. Pat. No. 3,405,499.
Difficulties are caused in the known closure apparatuses in particular due to the function of the clutches which are susceptible to wear and which suffer from a wide range of variation in regard to the maximum torque values, particularly under the fluctuating environmental conditions to which bottle filling plant is exposed. In addition, the clutch arrangements are expensive to construct, require frequent adjustment and setting and are susceptible to trouble.